Expansion rivet



Feb. 1, 1944. B. T. osHAUGHNEssY, JR., Erm. 2,340,423

EXPANSION RI'VET Filed Sept. 3; 1942 l Patented Feb. 1,1944

EXPANSION BIVET rnard T. OShauglmessy, Jrlhllartford, and Charles H.Desso, Manchester, Conn.

Application September 3, 1942, Serial No. 457,179

1 Claim. ('Cl. 85-40) Our invention relatesvto the class offasteningdevices comprising two members which may be separated to release thestructures which are held by them, and an object of our invention, amongothers, is the construction of a rivet of this type of simpleconstruction and which will eifectively accomplish the purpose for whichit is to be em v One form of an expansion rivet embodying the inventionand in the construction and use of which thev objects herein set out, aswell as' others, may be attained is illustrated in the accompanyingdrawing, in which- Figure 1 is a perspective view ofthe two parts of therivet separated but in relative positions for being united.

Figure 2 is -a view in section through the socket member of the rivetillustrating the manner of use, the plugv member being shown in positionfor insertion into the socket member.

Figure 3 is a view in section through the socket member showing the plugmember in place and the rivet conditioned for fastening two piecestogether. Y

While rivets embodying our invention may be -used in structures ofvarious types where it is desired to secure two members together, andespecially in a manner to provide for separation of the rivet parts topermit loosening of the fastened members, the invention is found to beespecially applicable in the fastening of cowls of aeroplanes inposition, but as above stated, the device may be used for fasteningvarious structures together and is therefore not limited in itsapplication for any` purpose forwhich it may be found applicable. y

In the accompanying drawing the numeralsli and 3 denote two pieces ormembers which are shown as fastened together by our improved expansionor separable rivet, these members each having a hole I through which thesocket member of the rivet is passed in the operation of securing thetwo parts together.

Th rivet comprises a socket member 8 and a plug member 9, the latterbeing adapted for insertion in the socket member as shown in Fig. 3. Thesocket member is of hollow formation and preferably round in contour incross sec-f tion. It comprises a. rim I0 of circular form and from whichspring arms II project, these arms, in normal and unrestrained conditionbounding an opening I2 of inverted frusto-conical shape of smallerdimensions at its inner than at its outer end. Each of theyarms at thoseends opposite the rim I0 is bent inwardly to create expending bends I3and from these bends the ends of the arms are bent outwardly as at I4and then backwardly to create clamping holders I5 the ends of which areadapted to abut against the fastened member `6 in opposition to the rimIU which is seated against the fastened member 5 when the rivet is insecuring position.

The plug member 9 may be of solid formation or it may be hollow, in thelatter case it being of suilicient strength to effectually resist anyforce tending to separate the fastened members 5 and 6 and consequentlyto separate the socket and plug members of the rivet. This plug memberis provided with a bead I6 extending around its outer end to limitinward movement of the plug within the socket 'member. An annular grooveIl is formed near the inner end of the plug member to receive theexpanding bends I3 at the inner ends of each of the spring arms I l thuscreating a circumferential expander I8 for the extremities of said armsand a retainer I9 on the opposite side of the groove Il -from theexpander I8 as shown in Fig. 3' of the drawing.

In the use of the rivet the socket member 8 is inserted through theholes l in the members 5 6, as shown in Fig. 2, with the spring arms Ilin converging relation inwardly from the rim Ill as shown in saidfigure.

v then inserted into the socket member and the expander I8 contactingwith the expanding bends I3 force the inner ends lof the spring arms I Ioutwardly into theposition shown in Fig. 3 thereby forcing the holdersi5 into close engagement with the surface of the member B and inopposition to the resistance of the rim I 0. In'this position theexpanding bends I3 at theends of the arms Il are located in the annulargroove I1 and the members 5-6 are thereby fastened securely together.

To loosen the members 5-6 a tool, as a screw driver, may Ibe forced inbetween the bead lI64 `that this lip may be dispensed with, and theengagement of the bends I3 with the groove I1 in the end of the plugmember will retain the plug member in place, the principal object of thelatter. being merely to force the arms Il outwardly into engagement withthe wall of the holes 7.

While the use of a tool, as a screw driver, thrust The plug member 9 isA 2 aia-10,423

underneath the lip I6 has been described 'as av` means for removing theplug mem-ber from thel socket member. when said lip is omitted any meansin the end of the plug member to be engaged by a suitable tool may` beemployed for removing the plug member from'the socket member.

In accordance-with the provisions of the patent statutes we havedescribed the principles of l operation of our invention together with'the' device which we now consider to represent the lbest embodimentthereof; but we desire to have it un derstood that the device shown isonly unistrative and that the invention may be carried out l0 means, aplug member of substantially cylindrical shape formed to fit-'within andenter said socket member and engage said arms to force said holders intoclose engagement with one of said objects and bring the axes of saidholders by other means and applied t0 uses other than 15 into straight.lines parauel to the axis of said those above set out.

We claim: An expansion rivet comprising a socket memf .ber having springarms of substantially even socket member, and interengaging meansbetween said arms and plug to restrain disengaging movement of said plugfrom within said socket member. BERNARD T. OSHAUGHNESSY, JR.

CHARLES H. DESSO.

